What are the other Names for this Condition? (Also known as/Synonyms)

• Autosomal Dominant Diffuse Palmoplantar Keratoderma, Norrbotten type
• Diffuse PPK, Bothnian type
• Non-Epidermolytic Palmoplantar Keratoderma

What is Diffuse Palmoplantar Keratoderma, Bothnian Type? (Definition/Background Information)

• Diffuse Palmoplantar Keratoderma, Bothnian Type is a rare type of hereditary diffuse palmoplantar keratoderma that is transmitted in an autosomal dominant manner. It is reported in people of north Sweden at a very high incidence rate
• Hereditary diffuse palmoplantar keratoderma is a type of palmoplantar keratoderma (PPK) caused by genetic mutations. PPK is a benign skin condition, wherein there is thickening of skin (keratoderma) of the palms and/or soles. PPK is considered to be a pattern of skin findings and not a condition in itself. The abnormal skin thickening can be focal (localized), widespread (diffused), or punctate type (appearing as tiny bumps)
• The treatment of Diffuse Palmoplantar Keratoderma, Bothnian Type involves the use of moisturizers, skin softeners, and systemic medications. The prognosis of the disorder is determined on a case-by-case basis, and may vary based on its severity

Who gets Diffuse Palmoplantar Keratoderma, Bothnian Type? (Age and Sex Distribution)

• Diffuse Palmoplantar Keratoderma, Bothnian Type is a rare congenital disorder. The incidence of the disorder is 1:40,000
• The signs and symptoms are noted in early childhood
• The condition affects both males and females
• All racial and ethnic groups may be affected; however, people in northern Sweden seem to have a high risk for the condition. The rate of occurrence is between 1 in 180-330 among this subset of Swedish population

What are the Risk Factors for Diffuse Palmoplantar Keratoderma, Bothnian Type? (Predisposing Factors)

• A positive family history may be an important risk factor, since Diffuse Palmoplantar Keratoderma, Bothnian Type can be inherited
• Children born to consanguineous partners or spouses may have a high risk for the condition
• A higher number of cases are reported among certain communities in north Sweden

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Diffuse Palmoplantar Keratoderma, Bothnian Type? (Etiology)

• Diffuse Palmoplantar Keratoderma, Bothnian Type is caused by genetic abnormalities which are passed down (through families) in an autosomal dominant pattern
• It is caused by mutations involving the AQP5 gene that is localized on chromosome 12

Autosomal dominant: Autosomal dominant conditions are traits or disorders that are present when only one copy of the mutation is inherited on a non-sex chromosome. In these types of conditions, the individual has one normal copy and one mutant copy of the gene. The abnormal gene dominates, masking the effects of the correctly function gene. If an individual has an autosomal dominant condition, the chance of passing the abnormal gene on to their offspring is 50%. Children, who do not inherit the abnormal gene, will not develop the condition, or pass it on to their offspring.

What are the Signs and Symptoms of Diffuse Palmoplantar Keratoderma, Bothnian Type?

The signs and symptoms of Diffuse Palmoplantar Keratoderma, Bothnian Type, may include:

• Presence of red palms and red soles
• This forms abnormally-thickened skin on the palms and soles, which is symmetric in presentation
• The skin thickening involves the entire palm and sole (diffused); the fingers and toes are usually affected
• A yellowish-waxy skin appearance is noted
• Grooves and deep cracks may appear on the palms and soles, due to drying and hardening of the skin layers
• No itching is noted, but there may be pain and inflammation
• Frequent fungal infections

How is Diffuse Palmoplantar Keratoderma, Bothnian Type Diagnosed?

Diffuse Palmoplantar Keratoderma, Bothnian Type is diagnosed on the basis of the following information:

• A complete evaluation of family and personal medical history along with a thorough examination of the skin lesions by a dermatologist
• Blood tests and fungal culture studies
• Dermoscopy: It is a diagnostic tool where a dermatologist examines the skin using a special magnified lens
• Wood’s lamp examination: In this procedure, the healthcare provider examines the skin using ultraviolet light. It is performed to examine the change in skin pigmentation
• Molecular genetic testing to identify the gene involved
• Skin biopsy: A skin biopsy is performed and sent to a laboratory for a pathological examination. The pathologist examines the biopsy under a microscope. After putting together clinical findings, special studies on tissues (if needed) and with microscope findings, the pathologist arrives at a definitive diagnosis

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Diffuse Palmoplantar Keratoderma, Bothnian Type?

The complications of Diffuse Palmoplantar Keratoderma, Bothnian Type may include:

• Scarring and disfigurement 
• Low self-esteem due to cosmetic concerns
• Secondary bacterial and fungal infections such as athlete’s foot
• Disruption of normal life and activities if the condition is severe

Complications may occur with or without treatment, and in some cases, due to treatment also.

How is Diffuse Palmoplantar Keratoderma, Bothnian Type Treated?

There is no cure for Diffuse Palmoplantar Keratoderma, Bothnian Type, since it is a genetic condition. The treatment is usually given to manage the signs and symptoms and any complication that develops. This may include:

• Use of moisturizing creams and lotions
• Use of oral medication such as acitretin or isotretinoin
• Antifungal therapy for secondary fungal infections
• Administration of keratolytics
• Vitamin D supplementation
• PUVA photochemotherapy
• Surgical debridement (removal of thickened skin), if required

Regular follow up visits with the healthcare provider is important and recommended.

How can Diffuse Palmoplantar Keratoderma, Bothnian Type be Prevented?

Diffuse Palmoplantar Keratoderma, Bothnian Type may not be preventable since it is a genetic disorder.

• Genetic testing of the expecting parents (and related family members) and prenatal diagnosis (molecular testing of the fetus during pregnancy) may help in understanding the risks better during pregnancy
• If there is a family history of the condition, then genetic counseling will help assess risks, before planning for a child
• Active research is currently being performed to explore the possibilities for treatment and prevention of inherited and acquired genetic disorders

What is the Prognosis of Diffuse Palmoplantar Keratoderma, Bothnian Type? (Outcomes/Resolutions)

• The prognosis of Diffuse Palmoplantar Keratoderma, Bothnian Type is dependent upon the severity of the signs and symptoms and associated complications, if any
• Individuals with mild conditions have better prognosis than those with severe symptoms and complications. Typically, the prognosis may be assessed on a case-by-case basis

Additional and Relevant Useful Information for Diffuse Palmoplantar Keratoderma, Bothnian Type:

The following DoveMed website link is a useful resource for additional information:

https://www.dovemed.com/healthy-living/skin-disorders/